/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.iotdb.tool;

import org.apache.commons.cli.*;
import org.apache.iotdb.cli.utils.JlineUtils;
import org.apache.iotdb.exception.ArgsErrorException;
import org.apache.iotdb.isession.SessionDataSet;
import org.apache.iotdb.rpc.IoTDBConnectionException;
import org.apache.iotdb.rpc.StatementExecutionException;
import org.apache.iotdb.session.Session;
import org.apache.iotdb.tsfile.exception.write.WriteProcessException;
import org.apache.iotdb.tsfile.file.metadata.enums.TSDataType;
import org.apache.iotdb.tsfile.fileSystem.FSFactoryProducer;
import org.apache.iotdb.tsfile.read.common.Field;
import org.apache.iotdb.tsfile.read.common.Path;
import org.apache.iotdb.tsfile.read.common.RowRecord;
import org.apache.iotdb.tsfile.write.TsFileWriter;
import org.apache.iotdb.tsfile.write.record.Tablet;
import org.apache.iotdb.tsfile.write.schema.MeasurementSchema;
import org.jline.reader.LineReader;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.util.*;

public class ExportTsFile extends AbstractTsFileTool {

    private static final String TARGET_DIR_ARGS = "td";
    private static final String TARGET_DIR_NAME = "targetDirectory";
    private static final String TARGET_FILE_ARGS = "f";
    private static final String TARGET_FILE_NAME = "targetFile";

    private static final String SQL_FILE_ARGS = "s";
    private static final String SQL_FILE_NAME = "sqlfile";
    private static final String QUERY_COMMAND_ARGS = "q";
    private static final String QUERY_COMMAND_NAME = "queryCommand";
    private static final String DUMP_FILE_NAME_DEFAULT = "dump";
    private static final String TSFILEDB_CLI_PREFIX = "ExportTsFile";
    private static String targetDirectory;
    private static String targetFile = DUMP_FILE_NAME_DEFAULT;
    private static String queryCommand;

    private static long timeout = -1;

    /**
     * main function of export tsFile tool.
     */
    public static void main(String[] args) {
        Options options = createOptions();
        HelpFormatter hf = new HelpFormatter();
        CommandLine commandLine = null;
        CommandLineParser parser = new DefaultParser();
        hf.setOptionComparator(null); // avoid reordering
        hf.setWidth(MAX_HELP_CONSOLE_WIDTH);

        if (args == null || args.length == 0) {
            System.out.println("Too few params input, please check the following hint.");
            hf.printHelp(TSFILEDB_CLI_PREFIX, options, true);
            System.exit(CODE_ERROR);
        }

        try {
            commandLine = parser.parse(options, args);
        } catch (ParseException e) {
            System.out.println(e.getMessage());
            hf.printHelp(TSFILEDB_CLI_PREFIX, options, true);
            System.exit(CODE_ERROR);
        }
        if (commandLine.hasOption(HELP_ARGS)) {
            hf.printHelp(TSFILEDB_CLI_PREFIX, options, true);
            System.exit(CODE_ERROR);
        }

        int exitCode = CODE_OK;
        try {
            parseBasicParams(commandLine);
            parseSpecialParams(commandLine);

            session = new Session(host, Integer.parseInt(port), username, password);
            session.open(false);

            if (queryCommand == null) {
                String sqlFile = commandLine.getOptionValue(SQL_FILE_ARGS);
                String sql;

                if (sqlFile == null) {
                    LineReader lineReader = JlineUtils.getLineReader(username, host, port);
                    sql = lineReader.readLine(TSFILEDB_CLI_PREFIX + "> please input query: ");
                    System.out.println(sql);
                    String[] values = sql.trim().split(";");
                    for (int i = 0; i < values.length; i++) {
                        legalCheck(values[i]);
                        dumpResult(values[i], i);
                    }

                } else {
                    dumpFromSqlFile(sqlFile);
                }
            } else {
                legalCheck(queryCommand);
                dumpResult(queryCommand, 0);
            }

        } catch (IOException e) {
            System.out.println("Failed to operate on file, because " + e.getMessage());
            exitCode = CODE_ERROR;
        } catch (ArgsErrorException e) {
            System.out.println("Invalid args: " + e.getMessage());
            exitCode = CODE_ERROR;
        } catch (IoTDBConnectionException e) {
            System.out.println("Connect failed because " + e.getMessage());
            exitCode = CODE_ERROR;
        } finally {
            if (session != null) {
                try {
                    session.close();
                } catch (IoTDBConnectionException e) {
                    exitCode = CODE_ERROR;
                    System.out.println(
                            "Encounter an error when closing session, error is: " + e.getMessage());
                }
            }
        }
        System.exit(exitCode);
    }

    private static void legalCheck(String sql) {
        String sqlLower = sql.toLowerCase();
        if (sqlLower.contains("count(")
                || sqlLower.contains("sum(")
                || sqlLower.contains("avg(")
                || sqlLower.contains("extreme(")
                || sqlLower.contains("max_value(")
                || sqlLower.contains("min_value(")
                || sqlLower.contains("first_value(")
                || sqlLower.contains("last_value(")
                || sqlLower.contains("max_time(")
                || sqlLower.contains("min_time(")) {
            System.out.println("The sql you entered is invalid, please don't use aggregate query.");
            System.exit(CODE_ERROR);
        }
    }

    private static void parseSpecialParams(CommandLine commandLine) throws ArgsErrorException {
        targetDirectory = checkRequiredArg(TARGET_DIR_ARGS, TARGET_DIR_NAME, commandLine);
        queryCommand = commandLine.getOptionValue(QUERY_COMMAND_ARGS);
        targetFile = commandLine.getOptionValue(TARGET_FILE_ARGS);
        String timeoutString = commandLine.getOptionValue(TIMEOUT_ARGS);
        if (timeoutString != null) {
            timeout = Long.parseLong(timeoutString);
        }
        if (targetFile == null) {
            targetFile = DUMP_FILE_NAME_DEFAULT;
        }

        if (!targetDirectory.endsWith("/") && !targetDirectory.endsWith("\\")) {
            targetDirectory += File.separator;
        }
    }

    /**
     * commandline option create.
     *
     * @return object Options
     */
    private static Options createOptions() {
        Options options = createNewOptions();

        Option opTargetFile =
                Option.builder(TARGET_DIR_ARGS)
                        .required()
                        .argName(TARGET_DIR_NAME)
                        .hasArg()
                        .desc("Target File Directory (required)")
                        .build();
        options.addOption(opTargetFile);

        Option targetFileName =
                Option.builder(TARGET_FILE_ARGS)
                        .argName(TARGET_FILE_NAME)
                        .hasArg()
                        .desc("Export file name (optional)")
                        .build();
        options.addOption(targetFileName);

        Option opSqlFile =
                Option.builder(SQL_FILE_ARGS)
                        .argName(SQL_FILE_NAME)
                        .hasArg()
                        .desc("SQL File Path (optional)")
                        .build();
        options.addOption(opSqlFile);

        Option opQuery =
                Option.builder(QUERY_COMMAND_ARGS)
                        .argName(QUERY_COMMAND_NAME)
                        .hasArg()
                        .desc("The query command that you want to execute. (optional)")
                        .build();
        options.addOption(opQuery);

        Option opHelp =
                Option.builder(HELP_ARGS)
                        .longOpt(HELP_ARGS)
                        .hasArg(false)
                        .desc("Display help information")
                        .build();
        options.addOption(opHelp);

        Option opTimeout =
                Option.builder(TIMEOUT_ARGS)
                        .longOpt(TIMEOUT_NAME)
                        .hasArg()
                        .desc("Timeout for session query")
                        .build();
        options.addOption(opTimeout);
        return options;
    }

    /**
     * This method will be called, if the query commands are written in a sql file.
     *
     * @param filePath:file path
     * @throws IOException: exception
     */
    private static void dumpFromSqlFile(String filePath) throws IOException {
        try (BufferedReader reader = new BufferedReader(new FileReader(filePath))) {
            String sql;
            int i = 0;
            while ((sql = reader.readLine()) != null) {
                legalCheck(sql);
                dumpResult(sql, i++);
            }
        }
    }

    /**
     * Dump files from database to tsFile.
     *
     * @param sql export the result of executing the sql
     */
    private static void dumpResult(String sql, int index) {
        final String path = targetDirectory + targetFile + index + ".tsfile";
        try {
            SessionDataSet sessionDataSet = session.executeQueryStatement(sql, timeout);
            long start = System.currentTimeMillis();
            writeTsFileFile(sessionDataSet, path);
            sessionDataSet.closeOperationHandle();
            long end = System.currentTimeMillis();
            System.out.println("Export completely!cost: " + (end - start) + " ms.");
        } catch (StatementExecutionException
                | IoTDBConnectionException
                | IOException
                | WriteProcessException e) {
            System.out.println("Cannot dump result because: " + e.getMessage());
        }
    }

    public static void writeTsFileFile(SessionDataSet sessionDataSet, String filePath)
            throws IOException, IoTDBConnectionException, StatementExecutionException,
            WriteProcessException {
        List<String> columnNames = sessionDataSet.getColumnNames();
        List<String> columnTypes = sessionDataSet.getColumnTypes();
        File f = FSFactoryProducer.getFSFactory().getFile(filePath);
        if (f.exists()) {
            f.delete();
        }
        HashSet<String> deviceFilterSet = new HashSet<>();
        try (TsFileWriter tsFileWriter = new TsFileWriter(f)) {
            Map<String, List<MeasurementSchema>> schemaMap = new LinkedHashMap<>();
            for (int i = 0; i < columnNames.size(); i++) {
                String column = columnNames.get(i);
                if (!column.startsWith("root.")) {
                    continue;
                }
                TSDataType tsDataType = getTsDataType(columnTypes.get(i));
                Path path = new Path(column, true);
                String deviceId = path.getDevice();
                List<Field> deviceList =
                        session.executeQueryStatement("show devices " + deviceId, timeout).next().getFields();
                if (deviceList.size() > 1 && "true".equals(deviceList.get(1).getStringValue())) {
                    deviceFilterSet.add(deviceId);
                }
                MeasurementSchema measurementSchema =
                        new MeasurementSchema(path.getMeasurement(), tsDataType);
                schemaMap.computeIfAbsent(deviceId, key -> new ArrayList<>()).add(measurementSchema);
            }
            List<Tablet> tabletList = new ArrayList<>();
            for (String deviceId : schemaMap.keySet()) {
                List<MeasurementSchema> schemaList = schemaMap.get(deviceId);
                Tablet tablet = new Tablet(deviceId, schemaList);
                tablet.initBitMaps();
                Path path = new Path(tablet.deviceId);
                if (deviceFilterSet.contains(tablet.deviceId)) {
                    tsFileWriter.registerAlignedTimeseries(path, schemaList);
                } else {
                    tsFileWriter.registerTimeseries(path, schemaList);
                }
                tabletList.add(tablet);
            }
            if (tabletList.isEmpty()) {
                System.out.println("!!!Warning:Tablet is empty,no data can be exported.");
                System.exit(CODE_ERROR);
            }
            while (sessionDataSet.hasNext()) {
                RowRecord rowRecord = sessionDataSet.next();
                List<Field> fields = rowRecord.getFields();
                for (int i = 0; i < fields.size(); ) {
                    for (Tablet tablet : tabletList) {
                        int rowIndex = tablet.rowSize++;
                        tablet.addTimestamp(rowIndex, rowRecord.getTimestamp());
                        List<MeasurementSchema> schemas = tablet.getSchemas();
                        for (int j = 0; j < schemas.size(); j++) {
                            MeasurementSchema measurementSchema = schemas.get(j);
                            Object value = fields.get(i).getObjectValue(measurementSchema.getType());
                            if (value == null) {
                                tablet.bitMaps[j].mark(rowIndex);
                            }
                            tablet.addValue(measurementSchema.getMeasurementId(), rowIndex, value);
                            i++;
                        }
                        if (tablet.rowSize == tablet.getMaxRowNumber()) {
                            writeToTsfile(deviceFilterSet, tsFileWriter, tablet);
                            tablet.initBitMaps();
                            tablet.reset();
                        }
                    }
                }
            }
            for (Tablet tablet : tabletList) {
                if (tablet.rowSize != 0) {
                    writeToTsfile(deviceFilterSet, tsFileWriter, tablet);
                }
            }
            tsFileWriter.flushAllChunkGroups();
        }
    }

    private static void writeToTsfile(
            HashSet<String> deviceFilterSet, TsFileWriter tsFileWriter, Tablet tablet)
            throws IOException, WriteProcessException {
        if (deviceFilterSet.contains(tablet.deviceId)) {
            tsFileWriter.writeAligned(tablet);
        } else {
            tsFileWriter.write(tablet);
        }
    }

    private static TSDataType getTsDataType(String type) {
        switch (type) {
            case "INT64":
                return TSDataType.INT64;
            case "INT32":
                return TSDataType.INT32;
            case "FLOAT":
                return TSDataType.FLOAT;
            case "DOUBLE":
                return TSDataType.DOUBLE;
            case "TEXT":
                return TSDataType.TEXT;
            case "BOOLEAN":
                return TSDataType.BOOLEAN;
            default:
                throw new IllegalArgumentException("Invalid input: " + type);
        }
    }
}
